Railroad ties have been made of wood for many years, sometimes treated with a preservative such as coal tar creosote and sometimes used without any treatment at all. The ties are mostly used outdoors and therefore are subjected to weathering and attack by insects and mold. Railroad rails are fastened to the ties by spikes or screw fittings and therefore the ties must be capable of resisting splitting and chipping at the area near the fittings. Railroad ties are also subject to high bending and compression forces each time a train passes over the ties. Wooden ties are adapted to withstand such treatment because of their fibrous composition and this feature is one reason why wood ties are preferred above steel and concrete ties. Because of its inherent resiliency, the body of the railroad tie of this invention is made of wood.
Creosote inhibits the growth of fungi and other molds but, with age, cracks appear in the wood tie and mold initiates rapid decay and rotting. It is estimated that the average life of a railroad tie is only fifteen years. The bonding of resin secured plies to the top and bottom surfaces of a wood tie substantially eliminates cracking and splintering of the wood tie and greatly prolongs its life. Also, the plies reduce splitting of the wood where the spikes are placed to secure the rails to the tie.